Isoteoline (IST) has been previously shown to possess anxiolytic activity in models of mice and rats. The aim of the present study was to examine this compound for potential memory-impairing and sedative effects. IST was compared with scopolamine and diazepam known for their anterograde amnesia, in respect to information acquisition. Diazepam served also as a sedative standard. Passive avoidance test was used to explore the effect of the drugs on the cognitive processes. Memory components such as acquisition, consolidation and retrieval were assessed depending on the time of drugs' administration relative to the training session and the retention session 24h later. We measured open field locomotion as an index of possible sedation. The results showed that IST was devoid of adverse effects on cognition. Unlike diazepam and scopolamine, IST tended to improve acquisition. It had no effect on memory consolidation and retrieval. IST did not reduce locomotion as well as thus differing from diazepam also in this respect. The lack of amnesic and sedative effects of IST adds favourably to its anxiolytic activity.
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